 <!DOCTYPE html>
 <html lang="en">
 <head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://unpkg.com/axios/dist/axios.min.js"></script>
 </head>
 <body>
    <h1>cors跨域</h1>
    <button id="btn">发送请求</button>
    <script>
        const btn =document.querySelector('#btn')

        btn.onclick =function(){
            axios.get('http://127.0.0.1:7778/user',{//为什么这里要用完整的路径，这个服务器不也是本地的服务器吗
                params:{
                    userId:'001'
                }
            })
        }

    </script>
 </body>
 </html>